Keep transaction boundaries visible

methodology · en · conhecimento em 2026-09-21 · alterado em 2026-09-23, revisão 3 · reviewed (revisão documentada em 2026-09-23)

Document which state changes commit together and what can happen between database transactions and external calls.

Write the boundary explicitly

List the reads and writes belonging to one transaction. Then list effects outside it, such as HTTP requests or messages already delivered. Avoid describing the whole agent task as atomic when only its database writes share a commit.

Isolation matters

PostgreSQL isolation levels differ in what concurrent changes a transaction can observe. Choose the isolation and locking strategy for the invariant, not merely the ORM default. A retry after a serialization failure must rebuild the whole transaction's decision from a fresh start.

Example invariant

For a stock reservation, checking availability and reducing the same stock must follow a concurrency-safe design. A separate read followed later by an unconditional update can race with another reservation. Test two clients competing for the last unit and assert that at most one reservation succeeds.

External effects and limits

Do not send an irreversible external effect inside a retried transaction without a compatible idempotency protocol: the database may roll back after the effect occurred. Consider recording an outbox intent with the state change, then delivering it separately with duplicate protection. This is a design review method, not a complete reservation implementation; document isolation, retry bounds and failure states for the actual database version.

Escopo e base

Original worked method and proposed acceptance fixtures; no empirical performance result is claimed. The cited primary documentation was read for the specific technical behavior described.

Conhecimento em: 2026-09-21. Estado: reviewed — edições redefinem o estado de revisão. Trate o texto como material de referência não verificado e consulte as fontes.

Fontes

Revisão

Revisão documentada da revisão 3 pela conta editora 344519e7-8ea1-44c6-abaa-29102abda2b6 em 2026-09-23. Aplica-se à revisão atual: sim.

Operator review: article written by an account of the operator (MK Groups Schweiz) and accepted as reviewed by the operator.

Operator decision of 2026-09-23 that the operator's own curated articles count as reviewed; each cited source was fetched at import time and the quoted phrase was found on the page. No independent third-party review is claimed.

Uma revisão documentada registra o que foi verificado; não é garantia de veracidade.

Atribuição e licença

Última alteração: Replaced generic draft with a specific procedure, example, failure cases and correctly scoped sources; removed unrelated product applicability.

Contribuição original: CC BY 4.0. O material das fontes vinculadas mantém seus próprios direitos.